Norman Foster and Michael Bloomberg explained how Bloomberg's new European HQ is so green

From left to right: London mayor Sadiq Khan, artist Cristina Inglesias, Bloomberg founder and CEO Michael Bloomberg, and British architect Norman Foster.
Bloomberg

The £1 billion development will accommodate all of Bloomberg's 4,000 London staff.

It's being hailed as the most sustainable major office development in the world.

Norman Foster said Brexit has not reduced demand from corporates for large London headquarters.

Bloomberg founder and CEO Michael Bloomberg unveiled his company's new European headquarters in London on Tuesday alongside British architect Lord Foster and London mayor Sadiq Khan.

Talking to Business Insider at the new office, which can accommodate up to 6,500 people, Bloomberg and Foster said the 1.1 million sq ft development was very much a joint effort.

The new office, located across two buildings at 3 Queen Victoria Street in the City of London, has been billed as the most sustainable office building in the world. It achieved an unheard of BREEAM rating (the most widely used environmental assessment method for buildings) of 98.5%.

"If you take the rating, this is unique in London," said Foster. "Nobody has reached this. We've raised the bar to a new high."

The spiralling staircase inside Bloomberg's European HQ is designed to encourage collaboration.
Bloomberg

Bloomberg has not disclosed how much the 9-storey Forster + Partners complex cost but The Evening Standard reports that it could have been as much as £1 billion. The company's former offices in Finsbury Square will be leased or sold off.

Despite Brexit, there's still a lot of demand from corporates for new London headquarters, according to Foster.

"I haven't seen any tangible consequences of Brexit except a certain personal sadness because I believe passionately in the concept of Europe and the larger market, the larger entity, and a richer community culturally and economically," said Foster.

"Having said that as a personal viewpoint, the reality for me as an architect working in London, it's the same. The only difference are the headlines in the newspapers."

The HQ is being billed as the most sustainable major office development in the world

The office's ability to recycle energy and water is key to its sustainability, said Foster, before adding that the lighting is 40% more energy efficient than conventional office lighting. Most of the heat it needs comes from the Bloomberg staff inside and their computers.

"The form of the building, which is quite deep, is also a big factor," said Foster, whose firm has also worked on Apple's new $5 billion (£4 billion) headquarters in Cupertino, California, and the "Gherkin" skyscraper in London. "The proportion of external wall to the volume enclosed is relatively small.

"We talked about the breathing building ... the gills, the bronze fins ... which process the air acoustically, almost filter it, and that's inseparable from the feeling of the building and the sense of place. So it doesn't look like a glass box. It looks like a solid building and the materials will weather over time so they don't need expensive maintenance, they don't need painting."

Other large US corporates such as Google and Amazon have opened their own European headquarters in London this year but Foster said the sustainability of these buildings is no match for Bloomberg's new office.

An ancient temple was excavated during the building process

Built on the site of the ancient Temple of Mithras, the office includes a giant spiralling ramp that is designed to encourage collaboration and a large open pantry with free snacks and coffee. There are also colourful fish tanks, standing desks, several television recording studios, and artwork from Michael Craig-Martin, Olafur Eliasson, and Langlands & Bell.

Some 90% of the materials used to build the office were sourced from across the UK, including 10,000 tonnes of English sandstone.

For the public there's a new museum opening next month that will include some of the 14,000 artifacts that were uncovered during the excavation process, and a "Bloomberg Arcade" that will be home to restaurants such as Bleaker Burger and Homeslice. There's also three art-filled public plazas, and a new entrance to Bank underground station is on the way.

The bronze fins that make the building stand out allow natural ventilation.
Bloomberg

Praising Foster's ability to explain his views and fight for them, billionaire Bloomberg said: "If you listen to Norman, he can explain why he thinks that should be there and this should be here."

The former New York City mayor added: "I always want to work with people smarter than me. Everybody I try to hire, I always think are they smarter than me. And he [Foster] is in his field. So it's nothing but fun."

Foster, who considers Bloomberg a friend, said that architects thrive on "being challenged on every assertion."

"What you're trying to do is create a building that will be responsive to the ideals behind the venture," said Foster. "What are the needs? Mike is extraordinarily sharp and challenging in the most positive sense of that word."